Blue sprat (Spratelloides gracilis), a small fish belonging to Clupeiformes, is known to deteriorate so rapidly that it is difficult to process, refrigerate or freeze. Lipid oxidation progressed more rapidly in refrigerated blue sprat than in horse mackerel. To elucidate the mechanism for the rapid oxidative deterioration in blue sprat, the water-soluble fractions from skin, viscera, ordinary and dark meats of blue sprat were compared their lipid peroxidation activities with those extracted from horse mackerel by incubation with linoleic acid. In contrast to horse mackerel in which only the dark meat showed a considerable prooxidant activity owing to hemoprotein, the skin, viscera and ordinary meat showed a remarkable activity in blue sprat. The lipid peroxidation activity in the skin and ordinary meat from blue sprat were labile to heating. While, the activity in scera was more stable to heattreatment. The prooxidant in skin preferentially oxidized free fatty acids over triacylglycerol or methyl ester. The occurrence of the rooxidant activity in various tissues especially in the skin was suggested to be responsible for the poor stability of blue sprat during storage.

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The MicroFoss methods for estimating viable count of aerobic bacteria and coliforms from various vegetables and fruits were evaluated. Total 130 of samples were tested using conventional methods such as plate count agar and desoxycholate-agar plate count (coliform count). Each samples were tasted using the MicroFoss total viable count (TVC) and Coliform medium. The correlation coefficients of standard curves were given in 0.7-0.9. And, the MicroFoss method has widely range of quantification that it was unnecessary for serial dilution of sample solution. The MicroFoss method can detect the larger the initial bacteria concentration, the shorter the detection time (D_t). In theologically, it was estimated to detect for 1 cell less than 18 hours by these standard curves. Therefore, the MicroFoss method may be extremely useful for quality control in food industries. The other side, we try to detect E. coli from cultivation water of sprout by the MicroFoss E. coli medium. In inoculation area, the MicroFoss method jointly with Durham's tubes method could detect E. coli for 1 day of cultivation water, though FDA was recommended strongly to test 3 days of cultivation water for sprout.

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The purpose of this study is to develop a new method of rice grain quality evaluation by using an imaging technique based on ultra-weak photon counting. Images of the ultra-weak photon emission from rice grain were acquired and analyzed. The photon emission from rice grain was very weak at room temperature but became detectable by imaging techniques when the measurement temperature was risen. We can acquire clear photon-counting images at 50°C with a 10-minute integration. Furthermore, the imaging technique clarified that there was significantly high photon emission from unripe grain (polished rice). As the results of spectrum analysis, there was a characteristic peak at 670-680nm in the photon emission of the rice.
We also measured photon emissions from different fat acidity rice grains prepared using various polishing rates. Brown rice had the highest fat acidity index, and the fat acidity index decreased with polishing. The ultra-weak photon emission was almost in proportion to the fat acidity index. We concluded that the fat acidity index (from 0 to 28 KOHmg/100g) of rice grain could be measured by analyzing ultra-weak photon emission without any complicated chemical analysis. The fat acidity index and the photon emission from rice with different storage periods were also correlated. These results demonstrated the possibility of evaluating rice-grain quality using ultra-weak photon emission.

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The development of a non-destructive method was attempted for the measurement of food weight change (i.e. moisture content change) in a freeze-dryer. An aqueous solution of 10% dextrin was used as a food sample. Changes in both weight and temperature of the sample were simultaneously measured during a freeze-drying process. The capacitance of sample was also measured using two stainless steel heating shelf boards as a pair of electrode plates.
Sample temperature histories varied with the sample position in the dryer. Sample temperature did not precisely indicate the freeze-drying state of the sample. Determining the endpoint of freeze-drying based solely on the results of sample temperature measurements remained practical problems. The capacitance change showed a good correlation with the weight change. Thus, it is feasible to monitor the weight of a sample during freeze-drying by measuring its capacitance

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The fermentation of cacao beans is an important process for the quality development, and it has great effect on cacao flavor. Cacao flavor is influenced by the place of production, because there are many varieties of fermentation methods depending on the areas, farmers, cultivars, seasons and so on. The object of this investigation was to make use of its for development in order to produce delicious and high quality cacao beans with strong antioxidative activity by studying the fermentation of the cacao beans in detail. In this paper, we investigated the changes of various compositions such as proximate compositions and polyphenol content and so on in Venezuelan cacao beans during the fermentation for total six days. The results were as follows. 1) The concentrations of proximate compositions, polyphenol, caffeine and theobromine contents except for acid value and lipid content decreased at the first half of the fermentation, and these concentrations did not change significantly after the fourth day. 2) The color tone of the cacao beans changed into the dark brown which took on red from purple during the fermentation. 3) The total polyphenol content decreased about 20%, and the (-)epicatechin content decreased to half during the fermentation. Therefore DPPH radical scavenging activity decreased during the fermentation. 4) The alkylpyrazines, which are one of the most important flavor for cacao beans, were included very slight in unfermented cacao beans and did not change until the third day, 2, 3, 5, 6tetramethyl pyrazine increased after the third day of the fermentation, remarkably. From the results in this study about Venezuelan cacao beans, it suggests that the changes of compositions concerned with the taste were almost finished at the first half of the fermentation period, and the cacao flavor and flavor precursor such as alkylpyrazines, in particular 2, 3, 5, 6tetramethyl pyrazine, were formed at the latter half of the fermentation period, and characteristic flavor of cacao bean was produced in that period.

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Antimutagenicity of dimethylsulfoxide ex-tracts from cultured and wild vegetables of Tohoku region on the Trp-P2 induced mutagenicity to Salmonella typhimurium TA98 was examined. Each preparation shows its char-acteristic antimutagenicity against the mutagenicity of Trp-P2. Swertia herb, hops, indigo plant leaves, mulberry root, and perilla seeds had strong antimutagenicity.

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